Method and apparatus for detecting gaseous fuel leakage through a gaseous fuel admission valve within an engine

摘要

A method of detecting leakage through a gaseous fuel admission valve of a dual fuel engine including at least one such gaseous fuel admission valve and a gaseous fuel shut off valve includes determining a liquid fuel rate when the engine is operating in a liquid fuel mode and the gaseous fuel shut off valve is closed. The gaseous fuel shut off valve is thereafter opened while the engine is operating in the liquid fuel mode. A liquid fuel rate is determined after the gaseous fuel shut off valve is opened and the liquid fuel rate determined before opening of the gaseous fuel shut off valve is compared with the liquid fuel rate determined after opening of the gaseous fuel shut off valve. A detonation level within the engine cylinder may also be checked to determine if such detonation level exceeds a predetermined level indicative of gaseous fuel leakage. The detonation level check may also be utilized in a spark-ignited engine.